1. Field of the Invention
The present invention relates to an imaging device, an imaging method and a program storage medium.
2. Related Art
Recently, accompanying increasing resolution of solid state imaging devices such as Charge Coupled Device (CCD) area sensors and Complementary Metal Oxide Semiconductor (CMOS) image sensors, there is a rapid increase in demand for information equipment with imaging functions, such as digital electronic still cameras, digital video cameras, mobile phones, and Personal Digital Assistants (PDAs, mobile data terminals). Information equipment with imaging functions such as those described above will be referred to in general as imaging devices.
Conventionally, plural images are captured at different focal positions with focus bracket imaging. The plural captured images (focus bracket images) are subjected to corresponding point detection and image deformation, and an image with a deep depth of field or an image with a shallow depth of field are generated by combining the deformed images (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2008-271240 and JP-A No. 2008-271241). Namely, a blur-controlled image or an omnifocal image that is in-focus over the whole image region is obtained from focus bracket images. However, the degree of blur in each of the images is different due to the focus bracket images having different focal positions to each other. Therefore, the degree of correlation between the images falls, and thus corresponding point detection tends to fail. This problem is significant in cases of “macro imaging” in which a subject is captured from close proximity.